3/20/98 - Pella Christian's Scott Huisman breaks free from a trap but is still blocked by Iowa Falls' Nick Collison and turns the ball over during their game at Veterans Memorial Auditorium. Register file photo

Nick Collison dunks for two of his 25 points against Oregon during the NCAA Midwest Regional final at the Kohl Center in Madison, Wis., Sunday, March 24, 2002. Kansas will advance to the Final Four with the 104-86 win over Oregon. Tom Horan/AP

Kansas forward Nick Collison (4) shoots over Holy Cross forward Tim Szatko, right, in the first half Nov. 19, 2002, in Lawrence, Kan. Collison scored 20 points to lead the Jayhawks to an 81-57 win over Holy Cross. Collison was named to the AP All Big 12 team. Orlin Wagner/AP

San Antonio Spurs' Tony Parker, left, of France, drives around Oklahoma City Thunder's Nick Collison during the first half of an NBA basketball game, Saturday, Jan. 1, 2011, in San Antonio. San Antonio won 101-74. Darren Abate/AP

LeBron James, right, scored 29 points in Miami's win over Nick Collison and Oklahoma City in Game 3 Sunday. AP
Oklahoma City Thunder power forward Nick Collison (4) and Miami Heat small forward LeBron James (6) react during the second half at Game 3 of the NBA Finals basketball series, Sunday, June 17, 2012, in Miami. Lynne Sladky/AP

Oklahoma City forward Nick Collison, right, dunks against San Antonio center Tim Duncan on Monday night. AP
Oklahoma City Thunder power forward Nick Collison (4) dunks against San Antonio Spurs center Tim Duncan during the first half of Game 5 in the NBA basketball Western Conference finals, Monday, June 4, 2012 in San Antonio. Eric Gay/AP

Collison retired in May 2018 after 15 years with the organization. Russell Westbrook, Thunder point guard and 2017 league MVP, attended his teammate's retirement party in downtown Des Moines. Collison's No. 4 has also been retired at Kansas, where he starred from 1999-2003 and was the Big 12 Conference player of the year as a senior. He led Iowa Falls to back-to-back Iowa state basketball championships in 1998 and 1999.

"I started in cold gyms in small towns in Iowa and ended up playing in more than 1,000 games over 15 years in the best league in the world," Collison said in his retirement announcement. "I've had an incredible run. I'm proud of my career."

The announcement was made with the help of Saturday Night Live comedian Colin Jost, who rattled off more instantly recognizable names before reaching Collison, who averaged5.9 points, 5.2 rebounds and 1 assist per game in his professional career.

“Nick Collison's career in Oklahoma City was unique. Unique in that he helped create the internal standards for work ethic, selflessness, citizenship and ‎professionalism for an organization that was starting from scratch. Unique in that as a role player, he embedded himself as a legacy player for the Thunder because of his consistency both in times of success and adversity and respect for his teammates and the organization,” said Thunder Executive Vice President and General Manager Sam Presti. “It is fitting that Nick will continue his unique and singular relationship with the organization by being our first retired number.”

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